DH2i DxEnterprise 20.0 Software: Extended Vhosts for AG Quick Start Guide

Download the PDF

Extended Vhosts for AG

This guide describes how to add an Extended Vhost (exVhost) to a DxEnterprise cluster and then add an availability group to the exVhost. DxEnterprise supports two types of Vhosts: Vhosts, which have nodes as members, and exVhosts whose members consist of other Vhosts. The exVhosts are designed for running an availability group (AG) across multiple HA instances. This gives users the ability to have HA on both the primary replica and secondary replicas for the AG while providing independent health monitoring and failovers of the HA instances and the AG.

Add an exVhost

To configure an exVhost, at least 2 HA instances will need to be configured beforehand. For more information on configuring an HA instance, please see the DxEnterprise Administration Guide under the section titled Add a Virtual SQL Server Instance.

NOTE: For SQL Server on Linux, SQL Server 2019 CU9 or later will need to be installed and virtualized.

DxAdmin

  1. Right-click on DxCluster and select Add virtual host.
  2. Add the name for the exVhost.
  3. Add the virtual IP for the exVhost. If no virtual IP is required, then supply “*127.0.0.1” to assign the local loopback address to the exVhost.
  4. OPTIONAL: Add a probe port for internal load balancer probing.
  5. Under Member Type, select VHOST.
  6. Add the desired Vhost members from the Available Members list to the Selected Members list.

DxCli– Run the dxcli cluster-add-vhost command.

Syntax

dxcli cluster-add-vhost <vhost> <vips> <nodes | VHOST:vhosts> [autofailback] [1-5] [ilbports]

Parameters

Name Description Required
vhost The name of the Vhost. True
vips The virtual IP(s) for the Vhost (comma separated list for multiples). True
nodes | VHOST:vhosts The node(s) or Vhost(s) to add (comma separated list for multiples). True
autofailback Set autofailback or leave blank if autofailback is not desired. False
priority The priority order of failover between Vhosts (1 is the highest and 5 is the lowest). False
ilb_ports Ports to use for internal load balancer probing (comma separated list for multiples). False

Example

dxcli cluster-add-vhost exvhost1 10.1.200.101
VHOST:vhost1,VHOST:vhost2 false 1 40001

Add an Availability Group to an exVhost

DxAdmin

  1. Right-click on the exVhost and select Add availability group.
  2. Add a name for the AGS.
  3. OPTIONAL: Select the Tunnel checkbox to automatically create tunnel connections between AG members. This is applicable for cross-site, cross-domain cluster topology joined through the DH2i Matchmaking Cloud service (match.dh2i.com).
  4. Verify that the correct instances are selected for each Vhost.
  5. Set the desired mirroring port (default is 5022).
  6. Verify that the correct Availability Mode is selected for each Vhost.
  7. Click OK to commit the changes

DxCli– Run the dxcli add-ags command.

Syntax

dxcli add-ags <vhost> <ags_name> <param1> <param2> <…>

<param1> :
<node_name|instance_name|sql_login|sql_pass|mirror_port|availability_mode|[tunnel_port]>
<param2> :
<node_name|instance_name|sql_login|sql_pass|mirror_port|availability_mode|[tunnel_port]>
<…> :
<node_name|instance_name|sql_login|sql_pass|mirror_port|availability_mode|[tunnel_port]>

Parameters

Name Description Required
vhost The name of the Vhost. True
ags_name The name of the availability group. True
param1 A set of parameters for the primary replica in the availability group. True
param2 A set of parameters for the secondary replica in the availability group. True
A set of parameters for each additional replica in the availability group. False
node_name The name of the primary replica member. True
instance_name The name of the instance. True
sql_login Leave blank. True
sql_pass Leave blank. True
mirror_port The mirroring port to use for the availability group (default is 5022). True
availability_mode Synchronous_commit, asynchronous_commit or configuration_only. True
tunnel_port The port to be used for tunnel connections (for cross-site, cross-domain replication). False

Example

dxcli add-ags exvhost1 ags1
“VHOST:vhost1|instance1|||5022|SYNCHRONOUS_COMMIT”
“VHOST:vhost2|instance2|||5022|SYNCHRONOUS_COMMIT”

References

Download the PDF